In broadband wireless communication networks of the next generation, especially in relay networks with a relay station (RS for short), solving the problem of inter-cell interference in the wireless communication networks has become a key factor to improve a user terminal (UT) throughput and an average user terminal throughput in a cell.
Currently, the methods such as interference randomization, interference coordination and interference elimination and etc. are put forward in projects of the Institute for Electrical and Electronic Engineers (IEEE for short) 802.16j of the U.S.A., of the International Mobile Telecommunication Advance (IMT-Advanced for short) and of the WINNER (Wireless World Initiative New Radio), to solve the problem of inter-cell interference. However, in order to achieve the purpose of solving the inter-cell interference, the interference in the system must be measured effectively and accurately. In order to solve the problem of effectively and accurately measuring the interference produced (introduced) in the system, various different technologies have been widely discussed in standardization organizations such as the 3rd Generation Partnership Project (3GPP for short) and IEEE802.16e and etc . . . Typical solutions are to add power control, flexible frequency reuse, macro diversity, inter-cell interference randomization with interference elimination and etc. to user terminals. Although such technologies can be used to improve system performance and thus effectively improve peak data rate, average cell throughput and cell-edge user throughput, the technologies usually result in loss of average sector throughput or increased complexity of receivers.
The MU-MIMO is a key technology put forward in the Long Term Evolution (LTE for short) of the 3GPP technology to effectively solve problems of the peak data rate, the average cell throughput, and the cell-edge user throughput. During implementing the MU-MIMO, effectively pairing user terminals is an important factor which determines the performance of the MU-MIMO. In the prior art, usually pairing user terminals can be achieved according to parameters, such as path loss, reported by the user terminals and by performing calculation via inherent formulas. However, as network topology is becoming more and more complex, interference environment undergone by the user terminals is also increasingly complex, and especially in the wireless networks of the LTE of the 3GPP. Such interference increasingly impacts on the environment of pairing users, thereby seriously affecting the performance of the MU-MIMO. How to more effectively and more accurately pair user terminals and improve the properties of the MU-MIMO has been a topic that must be solved.